Too often we go into an attic and find the exact opposite though. But what causes roof sheathing to get discolored? Here are a few reasons why:
- Ventilation. Inadequate ventilation causes exterior mold spores to enter the attic, but does not allow them to leave. When the ventilation is not working properly, then there is also a buildup of heat and moisture as well. Thus, mold issues. It darkens the wood and can cause thousands of dollars in damage.
- Leaking. This is an easy one. If you have roof leaks, then the moisture stains the wood. And is you have a combination of issue #1 and #2, then that is a recipe for disaster.
- Old Age. As wood ages, it simply gets darker and discolored. It is usually not anything serious - just a fact of life.